12398779639 has 2 divisors, whose sum is σ = 12398779640. Its totient is φ = 12398779638.

The previous prime is 12398779607. The next prime is 12398779693. The reversal of 12398779639 is 93697789321.

It is a happy number.

Together with next prime (12398779693) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12398779639 - 2⁵ = 12398779607 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12398779699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6199389819 + 6199389820.

It is an arithmetic number, because the mean of its divisors is an integer number (6199389820).

Almost surely, 2^12398779639 is an apocalyptic number.

12398779639 is a deficient number, since it is larger than the sum of its proper divisors (1).

12398779639 is an equidigital number, since it uses as much as digits as its factorization.

12398779639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30862944, while the sum is 64.

It can be divided in two parts, 1239 and 8779639, that added together give a palindrome (8780878).

The spelling of 12398779639 in words is "twelve billion, three hundred ninety-eight million, seven hundred seventy-nine thousand, six hundred thirty-nine".